244 Browne.—A Second Contribution to our Knowledge of the 
downwards, and some horizontally in both cones. In Series B and C the 
average divergence of the traces is still a downward one. In both cones 
this average downward divergence is greater in the upper of the two whorls ; 
this seems to be an exceptional feature, found by coincidence in both cones. 
In Cone A the average divergence of the traces of Series D is upwards, 
while in Cone B this series has an average divergence downwards. 
One of the most striking facts brought to light in this table is that the 
average downward divergence of the traces in Series A is very much greater 
Text-fig. i. Divergence of traces of Series A of Cone B. x i3§. a.v.b, = axial vascular 
bundle; C. = cortex ; e. = epidermis; sp . = sporangiophore. 
(rather more than three times as great) in Cone B than in Cone A. In 
mature cones of Equisetum maximum the sporangiophores of the lower 
whorls are often markedly reflexed; such reflection presumably causes 
a considerable f pull * on the vascular strand passing through the cortex. 
It would seem very probable, therefore, that the greater extent of the 
downward sweep is the direct result of this ‘ pull \ It is true that many 
of the sporangiophores of Series B of Cone B were reflexed, and their 
traces seem to have been but little affected by the pull; but it must 
be remembered that the thickness of the cortex in this region of Cone B is 
